Heatbed temperature
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how can I adjust the correct temperature for heating bed?
if I set 60 and measure with ir thermometer then bed has only 45 degrees -
If the bed is glass, it's normal for the temperature on the top to be 5C to 10C lower than the bottom where the thermistor is.
Have you set the correct B value for the bed thermistor you are using, in the M305 P0 command?
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M305 P0 R4700 H0 L0
but I do not know if it is right
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I have now resisted 100k
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There is no B parameter in your M305 P0 command, so the firmware is using the default value of 3988. Do you have any information about the bed thermistor in your printer?
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I have silicone mat, aluplatte, glass
M305 P0 T100000 B3988 R4700 H0 L0
is it right? -
resistance of thermistor has 103k
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if it is the std Chinese type Silicon mat then they usually have a thermistor with a B Value of 3950 but this is at temps of 25/50 I used DC42's calculator and it gave a B value of 4008 for the typical temps of 100 degrees.
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yes, silicone mat is from china
M305 P0 T100000 B4008 R4700 H0 L0it is OK?
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Yes. However, increasing the beta value in M305 will reduce the temperature reading, for temperatures above 25C. So try B3950.
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Now I have set 70 degrees and have 62.
can one adjust more exactly? -
Is that 62 measured with your IR thermometer? If so, then how accurate is your IR thermometer? They can often be quite a way out.
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also bare in mind that with these Silicon heaters the thermistor is usually on the underside of it and is below the bed itself so you will get a difference anyhow but you can adjust the B Value to get it closer to what you want but As Ian (Deckingman) has pointed out do you know your IR Thermometer is accurate I would use a multi meter with a Thermocouple probe that is in very close contact with the top of the glass
